14 BOTANY. ?edges as a forage, the stock in the San Luis Valley thrives the year around on them. There, over thousands of acres, these plants grow more than four feet high. Irrigation is possible anywhere in this first division, and water (slightly brackish) is usually obtained by digging a few feet. The second division is made up of the higher ground, beyond reach of irrigation. The soil and its productions undergo a complete change. Grama,* chico, and greasewood are here the prevailing growth. The soil is unpromising in appearance, yet would, if irrigation were possible, pro¬ duce fair crops. It will not be likely to be brought un^der the domain of agriculture for many years. Most propitious seasons are, in the absence of water, absolutely required for this kind of soil. It is, however, the legitimate sheep-walk of the valley. The third division are the sand-wastes, where there is no water and almost no vegetation. Even the chico and sage-brush are barely able to live there. I know of no use to which it can be put. There are some sheep occasionally found on it, but they derive most of their subsistence from the adjacent vega, or lowland. It is known, also, that in the smaller valleys between spurs of the mountains, bunch-grass is found in considerable quantity. The pinon- groves furnish shelter and a certain amount of grama during the winter for the herds that frequent them. From Loma, south, wheat has long been a regular crop. Corn, too, produces small ears with certainty at Conejos. It is not unlikely that they could be increased in size by the introduction and thorough acclimation of better seed. * The term Grama, now applied to the various species of Bouteloua in our Southwest, evidently comes from Spain. It is there applied to what we know here as Bermuda, or Souicli-Grass {Cynodon Dactylon, Pers.), introduced among us from Southern Europe, and also found now widely distributed over the warmer parts of the globe. Gramma is incorrect, and grass, as a suffix, is superfluous. The use of the name was evidently suggested here by the one-sided arrangement of the spikelets,—so like that in Cyno¬ don Dactylon.